Macroevolution

Question 1

What is macroevolution?

Answer 1

Evolution over geological time of groups larger than 1 individual

Question 2

Speciation?

Answer 2

Process of how a new species evolves

Question 3

Biological species

Answer 3

Group of organisms that can reproduce with one another in nature and produce fertile offspring

Question 4

How do new species arise?

Answer 4

Some members of a species must become reproductively isolated from the rest of the species, when two populations are separated their allele frequency changes. Since they no longer have migration between the population two separate species develop

Question 5

Allopatric Speciation

Answer 5

When GEOGRAPHICAL BARRIERS divide a population, followed by the development of mechanisms in the separate populations that prevent interbreeding

Question 6

What is the most important factor in starting speciation

Answer 6

Geographical Isolation

Question 7

PHYSICAL AND BEHAVIOURAL CHANGES

Answer 7

• develop and keep 2 species isolated from interbreeding… ex. shrimp between the carribean seas have become different species and communicate, collect food, etc. diff.

Question 8

Reproductive isolation

Answer 8

• formed by geographical isolation
• any factor in nature that prevents interbreeding
  (breeding in a close population) between individuals of the same or closely related species

Question 9

Extrinsic Isolating Mechanism

Answer 9

Outside of the organisms In question EX. GEOGRAPHIC ISOLATION

Question 10

Intrinsic Isolating Mechanism

Answer 10

Internal characters that prevent interbreeding
Diff in anatomy, physiology, and behaviour
ECOLOGICAL, TEMPORAL, BEHAVIOURAL, MECHANICAL, GAMETIC, HYBRID INVIABILITY

Question 11

Ecological Isolation

Answer 11

When 2 species have diff habitats they will rarely have contact…
Ex. Lions–grasslands, tigers–forests
Liger- won’t survive in the wild, not meant to exist

Question 12

Temporal Isolation

Answer 12

• 2 species that share the same habitat but dont mate within the same time grame
• 2 populations of the same species of plant release their pollen at diff time of the year, if their reproductive periods didnt overlap they would’ve reduced gene flow

Question 13

Behavioural Isolation

Answer 13

• even if populations are in contact and breeding can occur, they must choose to mate
• such a choice is based on SPECIFIC COURTSHIP AND MATING DISPLAYS
  Ex. Albatrosses are behaviourally isolated from other bird species by their elaborate species—specific courtship behaviour

Question 14

Mechanical Isolation

Answer 14

Reproductive organs differ in size/shape/another feature
Diff species of alpine butterflies look similar but have different reproductive organs

Question 15

Gametic Isolation

Answer 15

Even if mating occurs, offspring may not result if there are INCOMPATIBILITIES between sperm and egg/sperm and female reproductive tract

Question 16

HYBRID inviability/infertility

Answer 16

Even if offspring develop, they’re most often MALFORMED or STERILE

Question 17

skip flashcard: for studying tmrw
- why cant hybrids survive and why are they sterile?

Answer 17

(skip)

Question 18

ALLOPATRIC SPECIES (EXTRINSIC)

Answer 18

Geographic barrier

Question 19

INTRINSIC

Answer 19

• invariability, eco, temp, gamete, mechanical, and behavioural

Question 20

SYMPATRIC SPECIATION

Answer 20

Occurs when there are no physical barriers preventing any members of a species from mating with each other and all members are in close proximity to another
- A NEW SPECIES (BASED ON DIFF FOOD SOURCE/CHARACTERISTIC) SEEMS TO DEVELOP SPONTANEOUSLY
Ex. Bacteria developing immunity to sanitizer

Question 21

How does Sympatric Speciation occur (????CHECK THIS ONE)

Answer 21

Polyploidy

Question 22

Speciation VIA hybridization

Answer 22

• where the sperm and egg come together and produce an offspring, rarely a healthy hybrid Is produced (FOR TMRW;…WHY?), sometimes successful in plants NOT ANIMALS

Question 23

POLYPLOIDY

Answer 23

ONLY 4 PLANTS
- multiplication of the normal number of chromosomes In an organism, most happens in self-pollinating plants

Question 24

WHEN DOES SPECIATION OCCUR

Answer 24

Whenever a group in species isolates and develops unique traits

Question 25

Generalists VS Specialists

Answer 25

G: can live in diff types of environments, can adapt easier S: specific diets, especially when food in scarce, must adapt or will die

Question 26

What does sympatric refer to?

Answer 26

When there is no geographic barrier but these mechanisms continue to work

Question 27

What is adaptive radiation?

Answer 27

Rapid emergence of species form a single species thats been introduced to a new environment ;; tend to develop niches

Question 28

Two contributing factors for speciation

Answer 28

Specialization of food sources and environment Migration to a new environment, especially if there is no competition

Question 29

Phyletic Gradualism

Answer 29

smaller changes over time

Question 30

Punctuated Equilibrium

Answer 30

Less gradual changes; spontaneous

Question 31

What do gradualism and equilibrium have in common?

Answer 31

Depends on their environment, organisms can leave an unsuitable environment for a new one and flourish and pass on genes

Question 32

Convergent VS Divergent Evolution

Answer 32

Convergent- when species have different ancestral origins but developed similar features (HOMO) Divergent- 2 separate species evolve differently from a common ancestor (VEST)